Pharmaceutical compositions containing kanamycin embonate

ABSTRACT

The present invention relates to an a bacteriostatic pharmaceutical composition containing kanamycin embonate.

United States Patent [191 Guadagnini et al. Jan. 1, 1974 PHARMACEUTICAL COMPOSITION S [58] Field of Search 424/181 CONTAINING KANAMYCIN EMBONATE [75] Inventors: Giuseppe Guadagnini, Sannazzaro [56] References Cited dei Burgondi; Franco Fabi, Milan, OTHER PUBLICATIONS .bOth of Italy The Merck Index, 8th Edition, 1968, Merck & Co., [73] Assignee: Pierre! S.p.A., Milano, Italy Rahway pages 597 and 1 Filedi 1972 Primary Examiner-Jerome D. Goldberg [2]] Appl NO: 237,575 AttorneyBacon & Thomas Related US. Application Data [57] ABSTRACT [62] 2'; 1970 The present invention relates to an a bacteriostatic pharmaceutical composition containing kanamycin 52 [1.5. CI. 424/181 embonata' [51 Int. Cl A61k 21/00 4 Claims, N0 Drawings PHARMACEUTICAL COMPOSITIONS CONTAINING KANAMYCIN EMBONATE -This is a division of application Ser. No. 62,147, filed example kanamycin sulphate, it has several advantages. Firstly, as kanamycin embonate is less soluble in water it is consequently less readily absorbed which enables a high concentration of the active compound to be Aug 7 1970, issued as us p 3,691,151 on maintained in contact with the affected surface for a Sept 12 1972 longer period of time. The salt also possesses a high ad- The present invention relates to a new insoluble salt sorbmg Power Supenor fact to that of vegetable of kanamycin kanamycin embonate and to a method charcoal as shown when the two substances are com- Of preparing the Salt pared usmg methylene blue solut1ons buffered to pH Kanamycin is a known water soluble basic antibiotic The absorblllg Power of lfanamycm el'nbonate with produced by Streptomyces kanamiceticus according to regal-d to bacteqal cultures l also Supenor to F of the procedure set forth by Umezawa et in the kaolin as shown in the following test: Two bacterialcu la of Antibiotics, Series A, 10, it tur.S,.the first one ofsalmonella tlphlmurlum which IS has been shown by S. Umezawa et al Journal of Anti- Sensmve to kanamyc m h Second one bimics Series A 11, 120421 (1958) to have the 15 bacter aerogenes Wl'llCh 1s reslstant to kanamycin, are lowing formula: incubated for 18 hours and then kanamycin embonate and kaolin respectively are added 1n amounts of 20 CHINE: GHOH mg./ml. each. The two resulting suspensions are shook o for 30, left to stand for 3 hours and finally aliquots of OH 20 the supernatants are collected and diluted with physiol i/l logic soltuion.

HO 0 47 OH The bacterial counts have been carried out by means on H of two techniques for each case showing the results reported in the table here below, With the first technique, the diluted solution has been used for inoculating Petri Kunalnycin can be seen from the above formula to have dishes containing trypticasesoy-agar and the number Your free amino groups per molecule and it may form of viable bacterial cells calculated. With the second acid addition salts with many acids. Kanamycin is orditechnique, the total number of bacterial Ccll (Vlflblc narily recovered from its fermentation broths and proand d ad) has e n calculated using a Burkcr appaduced commercially in the form of its monosulphate. ratus.

Petri dishes Burker Bac. ct. Difs. 13210. et. Difs. Initial after of bae. Iutial after of bee. bacterial treatcount in bacterial treateountin count ment percent count ment percent Kanamycinembonate:

lsttest: S.tiphimurimn 2. 3x10 2.1 10 99 3x10 2. 95x10 99 2 udtest:/1.aemgenex 6X109 1.2X10 80 6.6)(10 1x10 85 i i test: S. tiphimurium 2.3X10" 5X10 78.4 3x10 7. 2X108 76 75 6.6X10 2.2 10 66.6

2nd test: A. aerogenes Kanamycin embonate, is a bacteriostatic substance, which has similar antibiotic properties to kanamycin, being effective against both Gram positive and Gram negative bacteria.

Kanamycin embonate is also less toxic and less water soluble than kanamycin itself and furthermore it is particularly effective in the treatment of intestinal diseases.

An important requirement for a product to be therapeutically active in the treatment of intestinal diseases, particularly of diarrheic ones, is that it should be possible to maintain a high concentration of active substance in contact with the affected part, substantially without absorption of the compound. It is also important that the pharmaceutical composition containing the active compound should have a high adsorbing power. A higher adsorbing power is usually obtained, or produced, in known compositions by adding to the active compounds a substance of a high adsorbing ability, as for instance vegetable charcoal or Kaolin which themselves are therapeutically inactive.

Kanamycin embonate has useful properties and in comparison w1th other known salts of kanamycin, for

The adsorbing properties of the new salts are combined with the antibiotic characteristics of kanamycin, and it is therefore possible to prepare pharmaceutical compositions that possess the necessary requirements for effective treatment of intestinal infections, without the necessity to add any other substance to the kanamycin embonate.

Kanamycin embonate can easily be prepared by any of the processes suitable for the preparation of salts.

In the process according to the invention a solution of a soluble salt of embonic acid, preferably the sodium or potassium salts, is reacted at room temperature with a solution of a soluble salt of kanamycin, preferably a sulphate.

The molecular ratio between the kanamycin and the embonic acid in the reaction medium should be 1:2 or more than 2. The kanamycin embonate precipitates and is separated by filtration and washed with water to remove the sulphate ions. The kanamycin embonate has the following characteristics:

embonic acid 61.6% kanamycin base 38.4%

Molecular weight: Contents:

Structural formula:

COOH ca,NH, c zmon OH x 0H OH H N n {b- 4) '1 on CH1 II H I OH IIQN NIIQ COOH Physicochemical characteristics:

Microcrystalline yellow powder Melting point (with decomposition): about 225C Practically insoluble in:

water, acetone, benzene, chlorform, diethylamine,

isopropylalcohol,

methylene chloride, pyridine, carbon tetrachloride Sparingly soluble in:

methyl and ethyl alcohols.

Soluble in:

Dimethylsulphoxyde, dimethylformamide, alkalies.

Antibiotic spectrum:

The antibiotic of spectrum of kanamyein embonate does not substantially differ from that of kanamyein sulphate. ln the following table we are reporting the data relative to the minimum inhibiting concentration of the two salts in comparison with various bacterial and fungal species. The minimum inhibiting concentration is given in y/ml. and it is expressed as activity referred to kanamyein base for both salts.

Kanamycin Sulphate (m .i.e. in y/ml.) 8

Kanamycin Embonate (m.e.c. in 'y/ml.) l I TEST GERMS S. Aureus ATCC 65388 B. cereus var. mycoides ATCC The LD of kanamyein embonate, orally administered (Sprague Dawley) is higher than 5000 mg/Kg. expressed as mg. of base per Kg. oflive weight.

ACUTE TOXICITY The acute toxicity was investigated in the mouse and rat by administering orally kanamyein embonate also at the maximum dose level of 5 mg./Kg. b.w. (body weight) per day (activity expressed as kanamyein base). No death occurred in 7 days of treatment.

SUB-ACUTE TOXIDITY The sub-acute toxicity was investigated in adult Albino rats of both sexes. Kanamycin embonate was administered orally at two dose levels: 150 and 400 mg./Kg. b.w. per day (activity expressed as kanamyein base), for 55 days.

The treatment produced a light decrease in growth rate and weight gains both in male and female animals, but the'following parameters were not affected: liver function (bromosulphaphthalein test), kidney function,

e.k.c., emopoietic system, bone marrow formation, blood N, blood glucose, serum proteins and gross histological examination.

CHRONIC TOXICITY A chronic treatment was investigated in Albino rats of both sexes by administering orally kanamyein embonate at two dose levels: 50 and 100 mg./Kg. b.w. per day (activity expressed as kanamyein base) for 180 days.

The treatment did not affect the following parameters: growth rate, blood N, blood glucose, emopoietic system, bone marrow formation, liver function, kidney function, e.k.c., weight gain and gross histological examination.

A chronic treatment was investigated in adult dogs by administering orally kanamyein embonate at two dose levels: 83 and I66 mg./Kg. b.w. per day (activity expressed as kanamyein base), for I days. The treatment did not affect the following parameters: weight gain, blood N, blood glucose, emopoietic system, bone marrow formation, kidney function, serum glutamic oxalacetic transaminase, serum glutamic piruvic transaminase, serum alkaline phosphatase, and gross histological examination of the main organs.

EMBRYOTOXICITY The embryotoxicity was investigated in rats and rabbits by administering orally kanamycin embonate at the maximum dose of I66 mg./Kg. b.w. per day (activity expressed as kanamyein base) from the 3rd to the 17th day of pregnancy inclusive.

The treatment did not affect the gestation and showed no noxious effect on the pregnant animals and on the embryo-fetal development.

OTOTOXICITY The ototoxicity was investigated by administering orally kanamyein embonate in Guinea pigs at the dose of mg./Kg. b.w. (activity expressed as kanamyein base).

The treatment produced no significative modification of the cochliovestibular function and of the histological structure of the interior ear.

ABSORPTION Kanamycin embonate adminstered orally is slightly absorbed by the gastroenterie walls and it can be absorbed only at very high dosage levels, however its absorption is always inferior than the absorption of equal dosage of kanamyein sulphate.

EXAMPLE OF PREPARATION A solution of 86.6 g. (0.2 moles) of sodium embonate in 2 l. of water is slowly added under stirring at room temperature, to a solution of 67.8 g. (0.1 mole) of kanamycin disulphate dissolved in 2 l. of water. A light' yellow precipitate is formed, which is then filtered, washed with water and dried under vacuum. 1 12 g. of kanamycin embonate, having the above reported characteristics and having an activity of kanamycin: 330-380 U/mg. are obtained.

PHARMACEUTICAL COMPOSITIONS kanamycin embonate per ml. depending from the particular formulation, together with suitable sweetening, flavouring, thickening or dispersing agents. For veterinary purposes, kanamycin embonate is administered orally in form of extemporary suspension or tablets at dosages depending from the kind of animals to be treated.

We claim:

1. A pharmaceutical composition comprising an effective bacteriostatic, non-toxic amount of kanamycin embonate in combination with a pharmaceutically acceptable excipient or carrier.

2. The composition of claim 1 in solid dosage form in which the amount of kanamycin embonate is from about 50 to 500 mg. per dosage unit.

3. The composition of claim l in liquid form in which the amount of kanamycin embonate is from about 0.5 g. to 5 g. per I00 ml of liquid.

4. The composition of claim 1 in tablet, capsule, suspension, syrup or drop form.

UNITED STATES PATENT OFFICE @ERTIFICATE 0F CURRECTIGN Patent No. 3 I 783 I 1 Dated January 1 1974 lnventofls) Giuseppe Guadagnini and Franco Fabi It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

IN THE SPECIFICATION:

Correct the formula top of column 3, as follows:

CHyNH,

CHQOH fif Day Of August1975 [SEAL] Arrest:

C. MARSHALL DANN ('mnmissimu'r of Parents and Trudcmurkx RUTH C. MAsON Allesling Officer 

2. The composition of claim 1 in solid dosage form in which the amount of kanamycin embonate is from about 50 to 500 mg. per dosage unit.
 3. The composition of claim 1 in liquid form in which the amount of kanamycin embonate is from about 0.5 g. to 5 g. per 100 ml of liquid.
 4. The composition of claim 1 in tablet, capsule, suspension, syrup or drop form. 